Define rust::isize with Windows support

gen/write.rs

@@ -110,6 +110,7 @@ fn write_include_cxxbridge(out: &mut OutFile, apis: &[Api], types: &Types) {
     let mut needs_rust_str = false;
     let mut needs_rust_box = false;
     let mut needs_rust_fn = false;
+    let mut needs_rust_isize = false;
     for ty in types {
         match ty {
             Type::RustBox(_) => {
@@ -124,6 +125,9 @@ fn write_include_cxxbridge(out: &mut OutFile, apis: &[Api], types: &Types) {
             Type::Fn(_) => {
                 needs_rust_fn = true;
             }
+            ty if ty == Isize => {
+                needs_rust_isize = true;
+            }
             ty if ty == RustString => {
                 out.include.array = true;
                 out.include.cstdint = true;
@@ -181,6 +185,7 @@ fn write_include_cxxbridge(out: &mut OutFile, apis: &[Api], types: &Types) {
         || needs_rust_box
         || needs_rust_fn
         || needs_rust_error
+        || needs_rust_isize
         || needs_unsafe_bitcopy
         || needs_manually_drop
         || needs_maybe_uninit
@@ -199,6 +204,7 @@ fn write_include_cxxbridge(out: &mut OutFile, apis: &[Api], types: &Types) {
     write_header_section(out, needs_rust_box, "CXXBRIDGE02_RUST_BOX");
     write_header_section(out, needs_rust_fn, "CXXBRIDGE02_RUST_FN");
     write_header_section(out, needs_rust_error, "CXXBRIDGE02_RUST_ERROR");
+    write_header_section(out, needs_rust_isize, "CXXBRIDGE02_RUST_ISIZE");
     write_header_section(out, needs_unsafe_bitcopy, "CXXBRIDGE02_RUST_BITCOPY");
 
     if needs_manually_drop {
@@ -689,7 +695,7 @@ fn write_type(out: &mut OutFile, ty: &Type) {
             Some(I16) => write!(out, "int16_t"),
             Some(I32) => write!(out, "int32_t"),
             Some(I64) => write!(out, "int64_t"),
-            Some(Isize) => write!(out, "ssize_t"),
+            Some(Isize) => write!(out, "::rust::isize"),
             Some(F32) => write!(out, "float"),
             Some(F64) => write!(out, "double"),
             Some(CxxString) => write!(out, "::std::string"),

include/cxx.h

@@ -180,6 +180,15 @@ class Error final : std::exception {
 };
 #endif // CXXBRIDGE02_RUST_ERROR
 
+#ifndef CXXBRIDGE02_RUST_ISIZE
+#define CXXBRIDGE02_RUST_ISIZE
+#if defined(_WIN32)
+using isize = SSIZE_T;
+#else
+using isize = ssize_t;
+#endif
+#endif // CXXBRIDGE02_RUST_ISIZE
+
 std::ostream &operator<<(std::ostream &, const String &);
 std::ostream &operator<<(std::ostream &, const Str &);